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排序方式: 共有726条查询结果,搜索用时 15 毫秒
1.
2.
Balloon dacryocystoplasty: indications and contraindications 总被引:3,自引:0,他引:3
3.
Duncan WC; Illingworth PJ; Young FM; Fraser HM 《Human reproduction (Oxford, England)》1998,13(9):2532-2540
The molecular mechanisms involved in luteolysis are still unclear in the
primate. This study aimed to investigate the effect of induced luteolysis
on the ovarian luteinizing hormone (LH) receptor and the steroidogenic
enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset
monkey. Luteolysis was induced in the mid-luteal phase either directly by
systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal
using systemic gonadotrophin releasing hormone antagonist (GnRHant)
treatment. The LH receptor was studied by isotopic mRNA in-situ
hybridization and in-situ ligand binding and 3beta-HSD expression was
studied using isotopic mRNA in-situ hybridization and immunohistochemistry.
Induced luteolysis was associated with a reduction in the expression of LH
receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a
reduction in the LH receptor (P < 0.05) and 3beta-HSD protein
concentrations within 24 h. There were no differences in the findings
whether luteolysis was induced with PGF2alpha or GnRHant. This study shows
that disparate mechanisms to induce luteolysis in the primate result in an
identical rapid loss of the LH receptor and 3beta-HSD. In conclusion,
induced luteolysis leads to rapid loss of the steroidogenic pathway in
luteal cells.
相似文献
4.
HM Clink 《Journal of clinical pathology》1980,33(8):799-800
5.
6.
Semen parameters and testicular pathology in men with testicular cancer and contralateral carcinoma in situ or bilateral testicular malignancies 总被引:2,自引:2,他引:2
Kliesch S; Bergmann M; Hertle L; Nieschlag E; Behre HM 《Human reproduction (Oxford, England)》1997,12(12):2830-2835
We evaluated 14 patients with bilateral testicular tumour, one-sided tumour
and contralateral carcinoma in situ (CIS) of the testis or testis tumour in
single testis with respect to their fertility. We analysed semen
parameters, serum hormones [follicle-stimulating hormone (FSH), luteinizing
hormone (LH) and testosterone], testicular sonography, testicular volumes
and testicular histology prior to further anti-cancer treatment. Ten out of
14 patients showed normal or reduced sperm concentrations, while 4/14
patients were azoospermic. Serum FSH levels showed a significant negative
correlation with sperm concentrations in patients with testicular
malignancies (r = -0.64, P = 0.025). Testicular volumes revealed a
significant positive correlation with semen parameters in patients with
testes that were affected by CIS (r = 0.733, P = 0.038). We conclude that
even bilateral testicular cancer and/or CIS do not preclude fertility and,
therefore, patients should be offered andrological investigation and
therapy, including possibly surveillance strategy or the chance for
cryopreservation of the semen prior to further treatment in order to
preserve their chances for paternity.
相似文献
7.
8.
Survey of CAG/CTG repeats in human cDNAs representing new genes: candidates for inherited neurological disorders 总被引:3,自引:2,他引:3
Neri C; Albanese V; Lebre AS; Holbert S; Saada C; Bougueleret L; Meier-Ewert S; Le Gall I; Millasseau P; Bui H; Giudicelli C; Massart C; Guillou S; Gervy P; Poullier E; Rigault P; Weissenbach J; Lennon G; Chumakov I; Dausset J; Lehrach H; Cohen D; Cann HM 《Human molecular genetics》1996,5(7):1001-1009
10.
OBJECTIVES: To determine the spectrum of N and G genotypes of respiratory syncytial virus (RSV) causing respiratory tract infection and whether particular genotypes are associated with severity of infection. PATIENTS AND METHODS: Nasopharyngeal aspirates (NPAs) were obtained from 114 infants with acute respiratory tract infection due to RSV over two seasons. Viral mRNA was extracted from NPAs or cultured virus, reverse transcribed, and the cDNA amplified by the polymerase chain reaction using primers directed to parts of the N and G gene respectively. Amplicons were separately digested with four different restriction endonucleases for each gene. The fragments were separated by agarose gel, electrophoresis, and the electrophoretic patterns used to assign the various genotypes. Disease severity was assessed as very mild (upper respiratory tract signs only), mild (coryza and signs of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: Five of the six known N genotypes were detected, but NP4 and NP2 were found most frequently. There was no association between N genotype and disease severity. Six G (SHL) genotypes were detected. Significantly (p = 0.04) more of the infants infected with the SHL2 genotype had severe or moderate disease. CONCLUSIONS: During the seasonal peaks of RSV respiratory tract infection at least 10 different RSV genotypes cocirculated. While there is no association between N genotypes and disease severity, infection with the SHL2 G genotype appears to result in moderate to severe disease. 相似文献